Wednesday, July 31, 2013

On this week's podcast, I met a few science fiction authors at Comic-Con International to see how they turn exotic science concepts into whole new universes, or just use basic science to make their work feel more realistic.

Tuesday, July 30, 2013

(ISNS) -- A heartbeat, or a pulse, is a standard indicator of whether a person or any other animal is dead or alive. But for a single biological cell, checking its viability – its state of being "alive" – is not that simple.

Knowing a cell's viability is valuable information in studying how an antibiotic works, how toxic substances kill cells and how an infection spreads. However, most viability tests for cells involve invasive procedures – such as injecting a dye into the cell. The tests are expensive and afterward, scientists have to dispose of the cells.

But now, a group of South Korean researchers have developed a non-invasive device that uses the cell's heat conductivity – its ability to act as a conduit for heat – to determine its viability.

Monday, July 29, 2013

The peak of summer has passed, and many students are slowly turning their minds to the upcoming school year. As back to school specials start hitting stores, many prospective students are hitting the books for graduate school entrance exams or poring over their scores from spring tests.

The most pervasive general graduate school exam in the U.S., the GRE, recently released its scoring data for the 1.5 years since a major overhaul of the test in late 2011. Within the dataset, the ETS has grouped average scores by the test-takers' intended graduate major, inevitably contributing to the bragging rights of "major" elitists.

So which majors reign supreme on the GREs? Let's have a look at the data for the test's three main sections: verbal, quantitative, and analytical writing.

Verbal Reasoning

The verbal section measures a student's critical thinking ability, reading comprehension, and vocabulary mastery through a series of multiple choice questions. The questions require students to complete sentences with the most fitting word or phrase available and glean information from short passages.

Here's how a selection of majors fared:

Data for tests taken between August 2011 and April 2013. These are a selection of representative majors, but you can find data for all majors in the ETS table. Source: ETS

Friday, July 26, 2013

1.2 million Americans live with HIV, more than 12.5 million have some type of cancer and 4.5 million are infected with hepatitis C. Researchers at the City Tech Lab located on the City University of New York campus are helping to detect diseases like these before the first symptom even appears.

Thursday, July 25, 2013

The Physics Central team had another successful year at Comic-Con International in sunny San Diego, CA. We distributed thousands of our Spectra comic books, reaching an audience that may otherwise miss out on the fun and excitement of physics.

We've collected some of our favorite photos from our time in the booth and exploring the weirdness of the exhibit hall. Take a look!

One of our team members fell victim to the force.
Image Credit: Mike Lucibella

One of the more colorful characters to stop by our booth.
Image Credit: Mike Lucibella

Wednesday, July 24, 2013

The HBO show Game of Thrones (based on the Song of Ice and Fire book series) takes place in a fictional world where magic and dragons make life a little more interesting for the people who live there. Set largely on the continent of Westeros, one notable characteristic of this world is it's seasonal cycle: winter and summer are of unpredictable duration. People there never know if a season will last for a few months or ten years.

Thankfully, here on Earth, the seasons run on a regular schedule. But astronomers are now finding that there may be planets in our universe where the seasonal cycles are more like that of Westeros. There are planets with highly eccentric orbits that could experience long, hard winters, and very brief summers; there are planets that orbit two (or more) stars, which may experience highly chaotic temperature fluctuations.

Today on the podcast I talk to two astrophysicists who are studying some of these odd planetary orbits. Veselin Kostov, a graduate student at Johns Hopkins University, studies circumbinary planets, but he is also a co-author on a recent paper that (very lightly) explores some hypothesis for how Westeros gets its seasons. Stephen Kane is an astrophysicist at the NASA Expolanet Science Institute. Kane coauthored a paper late last year (and on the arxiv) which examined how the surface temperature would fluctuate on a planet orbiting two stars.

Making small adjustments can improve an entire system's state

(ISNS) -- From the World Wide Web to the electrical grid, networks are notoriously difficult to control. A disturbance to just one part of the system can spread quickly and affect the whole thing. But this problem is its own solution: by selectively damaging part of the network, we can bring the entire system to a better state.

Image Credit: Andrew Imanaka via flickr

Why is it so important to manipulate networks? These complex systems pervade our everyday lives, from telecommunications systems to the connected neurons that form memories in your brain.

Unfortunately, nudging just a few nodes of a network can cause the entire system to malfunction. Take the electrical grid: A few downed power lines can trigger widespread blackouts. And it takes a lot of work and expensive materials to fix the broken components.
Read the rest of the post . . .

Wednesday, July 17, 2013

Glass is such a unique substance, scientists are still learning a lot about its fundamental nature even though we've been making it for thousands of years. On this week's podcast I talked to Douglas Allan a researcher at the Corning glass company. He and his teammates recently published an article in Physical Review Letters where a big piece of glass shrank by about 10 microns. He told me why that tiny change is such a big deal.

A new study, published in the Proceedings of the National Academy of Sciences,
shows that carbon-14, a radioactive version of the common carbon atom,
can be used to determine when an animal died to within about one year.

Monday, July 15, 2013

The varied worlds of comic books, fantasy, cartoons, anime, video games and blockbuster movies will converge in San Diego later this week for Comic-Con International 2013. We'll be there too, adding a little physics to the chaos of the convention.

During the school year, we distribute our educational (yet fun!) comic books and demo kits to middle schools across the U.S. After receiving great responses from teachers and students alike, we decided to extend our reach to the annual Comic-Con audience.

For the past few years we've been bringing our comic books, buttons, stickers, LED lights, and physics know-how to the busy San Diego Convention Center — the host of Comic-Con International. When we're not promoting our physics goodies at the convention, you can find us fighting crime and saving the day as evidenced by the image below from last year.

The Physics Central team at last year's Comic-Con. Muscles are only slightly exaggerated.Image Credit and Copyright: David Ellis

Thursday, July 11, 2013

(ISNS) -- A group of physicists and biologists has developed a nanotechnology-based technique that promises to increase the speed and sensitivity of diagnosing Lyme disease, a bacterial condition that infects more than 30,000 Americans each year.

The method, still in the research stage, uses nanotubes – tiny threads of carbon barely visible to the human eye – attached to antibodies that react with particular proteins carried by the bacteria responsible for the disease.

"We're looking directly for the Lyme organisms," said physicist A. T. Charlie Johnson, who led the multidisciplinary group at the University of Pennsylvania with bacteriologist Dustin Brisson. "This could be very useful in detecting early-stage infection."
Read the rest of the post . . .

In March, a paper published in Geologycreated a stir when it implicated waste-water injection as the likely cause of a 5.7 magnitude earthquake that occurred in Oklahoma. The November 2011 quake (one of three in a series) was the largest earthquake on record in the state. It destoryed 14 homes and injured two people.

The Oklahoma earthquake is also the largest seismic event to be linked to human activity, but unfortunately, that link remains tentative: the scientists who investigated the quake can't say for sure if the wastewater injection caused it, because they are lacking critical information about when, where and how much water was injected into the ground near the earthquake's source. Without that detailed history, it's impossible to conclusively implicate injection as the earthquake's cause.

Moving forward, the scientists say they'd like companies to keep track of that information and make it available. But, there is reason to believe some companies wouldn't agree to release that information unless they were legally required to do so. If the company's activities did cause an earthquake, they might be liable for the damage the quake caused, and it could tarnish the company's reputation. (It's important to note that the vast majority of waste water injection instances do not lead to seismic activity).

Tuesday, July 09, 2013

When sunlight hits a solar panel, a lot of it bounces right back off and its potential to be turned into electricity is lost. However a team of researchers in China and Sweden designed a simple but effective new solar cell design that captures much of that reflected light, potentially tripling the amount of energy that could be captured per square foot.

The team built an inverted pyramid solar cell to capture more light.
Image: Lintao Hou

The team's design essentially turned a small pyramid inside-out, and coated its inside with a kind of flexible solar cell. They built and tested four different pyramids with progressively sharper "peaks" to measure how they compared to traditional flat solar cells.

Monday, July 08, 2013

As the fireworks and festivities of this long fourth of July weekend have faded, many Americans are either trudging back to their offices with a food coma or embracing the week with a fervor that only a patriotic afterglow can provide. For the latter group, we've got some patriotic math research to report.

Although no new states have joined the U.S. for over half a century, there's been a renewed push to induct Puerto Rico as the 51st state. This fact coupled with the ongoing campaign for D.C.'s statehood raises the possibility of a new state and, consequently, the need for a new U.S. flag.

So what would a 51-star flag look like? Mathematician Skip Garibaldi (Emory University) answered that question with a computer simulation, revealing several possibilities. So what's the best 51-star flag? That depends upon your aesthetic preferences.

Stars can be arranged in a rectangle, circle, star, or some combination thereof. Check out the video below to see just a few of the options.

Wednesday, July 03, 2013

Today on the podcast I'm talking with Matthew Pennybacker, a mathematician who studies patterns in plants. In his most recent work, Pennybacker and his colleague Alan Newel have provided a mathematical description of the beautiful, swirling patterns that we see in sunflower heads.

Notice that the spirals on the sunflower head go in two directions: clockwise and counterclockwise. The number of spirals going in either direction usually differs on a single flower, and the number of spirals certainly varies from flower to flower; BUT the spirals still follow a regular pattern*: the number of spirals are almost always variables from something called the Fibonacci sequence.

The Fibonacci sequence starts with numbers 1 and 1, and then proceeds as such: each new number is the sum of the last two numbers. So the sequence goes: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89 and so on. Now why on earth would plants want to exhibit such a pattern in the way they organize their seeds? And how does the sunflower know that the seeds are being put in the right order? Listen to the podcast to find out! PLUS you'll hear how this mathematical understanding of plant patterns could actually teach us something about human development, convection in the atmosphere, and hard drives.

Tuesday, July 02, 2013

Scientists have developed a way to harvest energy generated by a swimming shark and turn it into electricity. A team of researchers at New York University stuck a strip of material that converts mechanical stress into electricity onto the tail of a robot shark and extracted usable energy from the simulated sea creature.

There's a whole family of materials that generate small amounts of electricity when crushed, flexed or knocked about. The most well known are piezoelectrics, which researchers have recently been looking into for ways to harvest otherwise wasted energy. A relative of piezoelectrics are electroactive polymers, which is what the scientists at New York University used.

Monday, July 01, 2013

An ongoing Kickstarter project has come up with the perfect recipe for a fun-filled, nerdy evening: quantum mechanics and board games. The people behind indie game company Elbowfish are trying to reach their $33,000 crowdfunding goal to distribute their physics-inspired board game called Antimatter Matters.

In the game, 2-6 Antimatter Matters players assume the roles of scientists in the not-too-distant future trying to assemble matter from stray elementary particles. The standard version of the game pits the scientists against one another in a race to create a hydrogen atom by collecting fundamental particles: electrons, quarks, gluons, and even photons.